Automatic slide projector



March 5, 1963 A. J. M MASTER ETAL 3,079,840

AUTOMATIC SLIDE PROJECTOR 11 Sheets-Sheet 1 Filed March 7, 1960 March 5,1963 A. J. MCMASTER ETAL 3,079,840

AUTOMATIC SLIDE PROJECTOR l1 Sheets-Sheet 2 Filed March 7, 1960 k .ffarZflax 75M I g; a

March 5, 1963 A. J. M MASTER ETAL AUTOMATIC SLIDE PROJECTOR l1Sheets-Sheet 3 Filed March 7, 1960 11 Sheets-Sheet 4 A. J. M MASTER ETALAUTOMATIC SLIDE PROJECTOR March 5, 1963 Filed March 7, 1960 March 5,1963 A. J. MGMASTER ETAL 3,079,840

AUTOMATIC SLIDE PROJECTOR Filed March 7, 1960 ll Sheets-Sheet 6INVENTORS. m I 1641 1 .Afazzzz ofefl March 5, 1963 A. J. MCMASTER ETAL3,079,840

AUTOMATIC SLIDE PROJECTOR Filed March 7, 1960 11 Sheets-Sheet 7 fiAwzm.

14; 11'' wzwnlw- March 5, 1963 A. J'. M MASTER ETAL AUTOMATIC SLIDEPROJECTOR 11 Sheets-Sheet 8 Filed March 7, 1960 A. J. M MASTER ETAL3,079,840

AUTOMATIC SLIDE PROJECTOR March 5, 1963 ll Sheets-Sheet 9 Filed March 7,1960 NE NM QR I INVENTOR; k

March 5, 1963 A. J. MGMASTER ETAL 3,079,840

AUTOMATIC sum; PROJECTOR 11 Sheets-Sheet 10 Filed March 7, 1960 3,t79,840 AUTGMATIC SILEE PRGJECTOR Archie J. Moll Easter, Bannoclrhurn,and Karl M. Maiershater, Nor-ridge, lll., assignors to 6-3/1Laboratories Inc Chicago, 111, a corporation of Illinois Filed Mar. 7,195%, Ser; No. 15,179 18 Claims. (Cl. 882ti) This invention relatesgenerally to projection apparatus for photographic slides and especiallyto automatically operated slide projectors.

Slide projectors heretofore constructed for automatic operation havebeen commonly adapted to receive quantitles of photographic slidesgrouped together in a desired sequence and carried by trays devised forthat purpose. These prior art slide projectors of the automatic typeordinarily drag or skid the photographic slide from the tray,subsequently levering it into position for projection. However, in theprocess of drag ing or skidding cardboard-mounted slides from and backto the trays, wearing of theedge of the slide takes place; and uponrepeated use of any particular slide, substantial wearing andconcomitant fraying of the edge of the slide develops. Slides so wornand disfigured are known to jam in the tray or in the projector itself,resulting in disruption of the slide show and inconvenience to both themachine operator and the audience.

When glass-mounted slides are used, the dragging or skidding causes theslides to score or groove the tray; and eventually, this damage mayprogress to the point that the tray is no longer suitable for itspurpose.

Accordingly, an important object of the present invention is to providean improved slide projector which overcomes the limitations of the priorart by lifting the individual slides from the tray.

A-mor-e general object of the invention is to provide a new and improvedslide projector of the automatic type.

A slide projector of the kind exemplified herein must necessarily besuitable for different styles of photographic slides; otherwise, its usewould be strictly limited. Hence, it is another object of the presentinvention to provide a slide projector which is suceptible of projectingsubstantially all commercially available styles of photographic slides.

Yet another object of the invention is to provide an automatic slideprojector which incorporates a compact drive.

A further object of. the invention is to provide an automatic slideprojector which is arranged to facilitate the editing of slides carriedin trays.

A still further object of the invention is to provide a slide projectorwhich is capable of both manual'and automatic operation.

Additional objects and features of the invention pertain to theparticular structure and arrangements whereby the above objects areattained.

A structure in accord with the invention includes support plate meansdefining a viewing frame; pusher arm means arranged with the supportplate means for arcuately transferring a slide to and from the viewingframe; clamp means confronting the pusher arm means in variablyspaced-apart relationship; mechanical means operably connectingthepusher arm means and the clamp means for permitting a slide to begripped selectively therebetween so as to implement tiltable lifting ofthe slide from-a slide tray and subsequent tiltable replacement thereof;indexing means on the support plate means adapted to advance the slidetray incrementally, the indexing means defining a stop abuttable withthe clamp means forcocking apart'the clampmeans and the pusher arm meansin order to release-the slide; control means pivotally mounted to thesupport plate means for operating the indexing means; axially movableshaft meansfor operating the mechanical means and the control means;clutch means on the shaft means engageable and disengageable by axialmovement thereof; a cam shaft rotatably mounted parallel to theoperatiing shaft means; a reversibly oscillatory member pivotallymounted about the cam shaft and adapted to mesh with a portion of one ofthe clutch elements in toothed engagement; planetary gear means arrangedto be driven by the cam shaft; cam follower means arranged with the gearmeans and adapted to ride in a cam slot defined in the oscillatorymember in order to oscillate that member in response to the rotation ofthe cam shaft whereby to drive the shaft means when the clutch means isengaged and whereby not to drive the shaft means when the clutch meansis disengaged; motive means for the cam shaft; switch means for slideprojector means disposed adjacent the cam shaft; and a plurality of camson the cam shaft adapted to operate the switch means selectively.

The invention, both to its structure and mode of operation, will bebetter understood by reference to the following disclosure and drawingsforming a part thereof, wherein a single embodiment of the invention isshown and wherein:

FlG. l is a perspective view of an automatic slide projector constructedin compliance with the invention;

FiG. 2 is a schematic wiring'diagram for the slide pro- -ector shown inFIG. 1;

E6. 3 is an exploded perspective view ofthe structure comprising thesupport plate assembly, the editing lever assembly, the shutter assemblyand the slide carrier bracket;

1G. 4 is another perspective view of the support plate assembly showingin particular'itsrelation with the means for biasing the editing leverassembly into a locked positlon;

PKG. 5 is a side-elevational view, taken through a central section ofthe slide projector of FIG. 1,. illustrating the support plate assemblywith the pusher arm and the slide clamp unit being spaced-apart as torelease a slide;

FIG. 6 is a side-elevational view, takenthrough a central section of theslide projector of FIG. 1, illustrating, in invisible outline, themain'drive lever'and the shutter and index control lever positioned incompliance with the showing of FIG. 5;

FIG. 7 is a perspective view of the drive pinion and its support member;

FIG. 8 is a side-elevational view, taken through a central section or"the slide projector of FIG. 1, showing the pusher arm means and theslide clamp means lifting a slide from the slide tray;

FIG. 9 is a side-elevational View similar to FIG. 8 illustrating, ininvisible outline, the drive lever and the shutter and index controllever positioned in compliance with the showing of FIG. 8;

FIG. 10 is a perspective view showing'the arrangement of the pusher armdrive lever and the main drive lever;

FIG. 11 is a side-elevational view, taken through a central section ofthe slide projector of FIG. 1, illustrating the pusher arm means and theslide clamp means positioned as they would be when they have transporteda slide into the viewing frame;

FIG. 12 is a side-elevational view similar to FIG. 11 illustrating, ininvisible outline, the main drive lever and the shutter and indexcontrol lever positioned as they would be when the pusher arm means andthe clamp means are disposed as shown in MG. 11;

FIG. 13 is a perspective view of the slide clamp means and the pusherarm means;

FIG. 14 is a view through the section 14-14 of FIG. 11;

FIG. 15 is a view through the section 15-15 of FIG. 8;

FIG. 16 is a View through-the section 16-46 of FIG. 11;

FIG. 17 is a View through the section 17-17 of FIG. 11;

FIG. 18 is a view through the section 1818 of FIG. 5;

FIG. 19 is a side-elevational View similar to FIG. 8 showing theconfiguration of the pusher arm means and the slide clamp means as theyinitially grasp a slide for tiltably lifting the same from the slidetray;

P16. 20 is a side-elevational view similar to FIG. 5 but showing theoperation of the editing lever;

FIG. 21 is a perspective view of the support plate assembly and stereoslide guide means, a stereo slide being shown in projection position;

FIG. 22 is a perspective view of the front plate of the stereo slideguide means;

FIG. 23 is a perspective view of the back plate of the stereo slideguide means;

FIG. 24 is a perspective view of the support plate assembly and the 2 x2 slide guide means, a 2 x 2 slide being shown entering the guide means;

FIG. 25 is a view of the support plate assembly and the 2% x 2 /4 slideguide means, a 2% x 2% slide being shown entering the guide means;

FIG. 26 is a bottom plan view of the automatic slide projector of FIG.1, showing the drive means of the invention;

FiG. 27 is an enlarged view taken through the section 27--27 of FIG. 26;

FIG. 28 is an enlarged view taken through the section 2823 of FIG. 26;

FIG. 29 is an enlarged, exploded perspective view showing portions ofthe planetary gear train employed in the drive means of the invention;

FIG. 30 is an enlarged view taken through the section FIG. 31 is anenlarged view taken through the section 31-3-1 of PEG. 26;

FIG. 32 is an enlarged view taken through the section 32-32 of FIG. 27;and

FIG. 33 is a further enlarged, perspective View showing the dog clutchthat is utilized in the drive means of the invention.

Referring now in detail to the drawings, specifically to FIG. 1, anautomatic slide projector is shown to include a projector structure 40to which a lamphouse 42 is swingably mounted. A control panel element 44upstands from the projector structure 40 confronting the lamphouse 42 soas to define therebetween a tray tunnel 46. The tray tunnel 46 isadapted to receive slide trays, such as slide tray 48, in a glidablemanner.

The lamphouse 42 is provided with a lamphouse lock knob 5t} and afocusing knob 52, the latter of which is adapted to operate a projectionlens assembly 54. However, since the lamphouse and its immediatelyassociated elements comprise no part of the present invention, they arenot illustrated in detail nor described further hereinbelow.

Turning now to FIG. 8, a support plate assembly 56 will be seen mountedat one location to a platform portion 58 of projector structure 41) bymeans of integral, laterally extending flanges 6G and suitablefasteners, such as bolt fasteners 62. Support plate assembly 56 ismounted at another location beneath the floor 64 of slide tray tunnel 46by means of integral, laterally extending flanges 66 and suitablefasteners, not shown. The support plate assembly 56 also defines anaperture or viewing frame 68 which extends into the optical path of theprojection system carried in lamphouse 42.

As will be seen from an inspection of FIG. 3, the support plate assembly56 is comprised of a first support plate 70 and a second support plate72 which is arranged to be substantially a mirror image of plate 70. Thesupport plates 79 and 72 are spaced-apart as by tubular spacerarrangements 74.

A number of elements are advantageously arranged in cooperatingrelationship between the support plates 70 and '72; and as shown inFIGS. 5, 8 and 11, among these elements is a pusher arm unit 7 6 whichincludes a pusher arm '73 and a pusher arm link 81 The pusher arm link81 defines a guide slot 82 and a cam slot 8 A pusher arm spacer roller86 is mounted between the support plates 71? and 72 and includes asuitable groove that receives the pusher arm link 86 at the guide slot82.

in order to provide motive force to the pusher arm unit 76, a pusher armdrive lever 88 is rotatably mounted between the support plates 76 and 72as by means of a suitably arranged hub 99. As shown in FIG. 10, thedrive lever 83 is comprised of two plates 92 and 94 which areadvantageously spaced-apart in order to permit the pusher arm unit 76 tooperate therebetween. Adjacent one end of the drive lever 83 is acylindrical cam follower 96 which is adapted to ride in the cam slot 84and thereby incur appropriate movements of the pusher arm unit On eitherside of the pusher arm unit 76, between guide slot 82 and cam slot 84,there is mounted a pusher arm slide bearing 98. Each of the slidebearings 93 is adapted to ride in a corresponding cam slot 199 fashionedin the juxtaposed support plate. The cam slots 1111) are aligned andcooperate with the guide slot 82 and the cam slot 84 in defining thepath and trace of movement realized by the pusher arm unit '76.

Continuing now with particular reference to FIG. 5, a slide clamp unitor back-up member 162 is swingably mounted in sandwiching relationshipto the end 164 of pusher arm unit 76 by means of a slide clamp bearing106. The slide clamp unit 192 resides between the support plates 78 and72 in confronting relationship with the end of pusher arm 78.

As will be seen in FIG. 13, the slide clamp unit 102 includes a pair ofspaced-apart slide clamp plates 108. A slide receiver is advantageouslyaifixed between these plates 1118 away from the bearing 106. Since theslide clamp unit 102 and the pusher arm 78 are adapted to grasp aphotographic slide 111 therebetween, the receiver 111 and the end of thepusher arm 78 are desirably fashioned with V-shaped slots, slots 112 and114 respectively, opening towards each other. As a further aid inproperly positioning the photographic slide 111 between the slide clampunit 162 and the pusher arm 78, a guide element 116 is appropriatelypositioned adjacent the bottom end of the V-shaped slot 112.

In accordance with a feature of the invention, the slide clamp unit 1112confronts the pusher arm 78 in variably spaced-apart relationship; andmeans which cooperate with the rotatable manner in which the unit 192 ismounted are provided for this purpose. These means include a pair oftension springs 118 which extend between monnting tabs 120 fashioned onthe slide clamp unit 1112 and a suitable bore 122 provided in the pusherarm unit 76. The springs 118 bias the slide clamp unit 1132 generallytoward the pusher arm 73; and as is best shown in FIG. 13, the pusherarm unit 76 is fashioned to provide a stop 124 which positivelyrestricts the movement of slide clamp unit 1112 in the general directiontoward pusher arm 78.

Referring now to FIG. 10, the pusher arm drive lever 83 will be seenfixed to a main drive lever 126 in spacedapart relationship by means ofthe hub 99 and a tubular spacer arrangement 128, the drive lever 126being disposed adjacent the outer side of support plate 72. As is shownin FIGS. 6, 9 and 12, the main drive lever 126 is adapted to operate ashutter and index control lever 130 and to index a slide tray drivepinion 132 by means. which will be described hereinbelow.

in order to operate the shutter and index control lever 5 130, the maindrive lever 7.26 is provided with a headed cam follower 134 mounted toan arm portion 135, a cam surface 138 on shutter and index control lever131 being adapted to be contacted by the shaft portion of cam follower134 between the arm portion 136 and the head of the cam follower 134.

The major portion of the cam surface 138 is arranged to coincide with tharc traversed by the cam follower 134. However, at its terminus 14%, thecam surface defines a stop which confronts the cam follower 134 wherebyfurther rotation of the main drive lever about a pivot 142.

Since the shutter and index control lever 13% extends a slot 1 .4 intoreceiving relationship with a shutter guide bushing 14d, this pivotingof the shutter and index control lever 13G incurs a vertically downwardmovement of .a shutter assembly 14-8 which is secured to the shutterguide bushing 146. In order to incur proper movements of the shutterassembly 148, the shutter guide bushing 1 rides in a guide slot 159fashioned in the support plate 72. A small stop plate 152 isadvantageously fixed to the free end of shutter guide bushing 14% inorder to prevent disengagement of the slot 144 and the bushing 14%; andstop elements 153 are desirably formed outwardly from plate 72, as shownin FIG. 11, to establish limits for the movement of lever 13d.

Returning to FIGS. 6, 9 and 12, it is to be recognized that verticallyupward movement of the shutter assembly 148 will be incurred by rotationof the cam follower 134 away from the terminal stop 1 2i and down thecam surface 138. The main drive lever 126 also includes a laterallyextending tongue 15d which is radially spaced from hub 3i? and which isadapted to confront one end of a pawl drive lever 156, the drive lever15% being rotatable about a pivot 15% that is mounted, as shown, to theshutter and index control lever 13d.

A drive pinion pawl Edi) is rotatably mounted to the shutter and indexcontrol lever 139 by means of a pivot 1 62 which is spaced-apart fromthe pivot 15%. The drive pinion pawl 166 is connected to the pawl drivelever 156 by means of a rivet 164 which is aiiixed to one end of thepawl tee and which is adapted to slide freely in a slot 156 which isfashioned in the pawl drive lever .156- A tension spring 163advantageously extends between a tab 176 provided on drive pinion pawl16st) and a tab 172 provided on the shutter and index control lever 339.Spring 163 establishes proper bias for the pawl drive lever 15 5 and thedrive pinion pawl 16E.

As is best shown in FIG. 18, the drive pinion pawl let? i is providedwith a feed pawl 174 which or ends laterally inwardly to be engageablewith the drive pinion 13.2 for purposes of indexin As best shown in PEG.7, the drive pinion 132 is rotatably mounted to a support member 375',preferably fabricated from nylon. A rivet 176 extends through the drivepinion 132 and a shoulder portion 173 of the support member 175.Advantageously, a washer 189 is interposed between the drive pinion 132.and the shoulder 178. The member 175 is suitably mounted between thesupport plates 79 and 72 as by a bolt fastener 182, shown in FIG. 5, anda stop extension 184 which extends from the shoulder portion 173 throughan appropriate aperture 186 provided in support plate 72. In addition tocooperating in the attachment of the support member 175, the stopextension 184 is arranged to limit that movement of pinion pawl 168which is urged by the bias of tension spring 168.

Considering FIG. 8 once again, the slide tray 43 will be seen to includea rack 188 which is adapted to mesh with the drive pinion 132 in toothedengagement. Thus, it will become apparent that, as the drive pinion 132is stepped or rotated incrementally by action of the feed pawl 174,slide tray 48 will be stepped or re-situated incrementally through thetray tunnel 46.

As can be seen in FIG. 18, a detent arrangement 19!) is provided toinsure proper incremental stepping of the drive pinion 132. The detentarrangement 1% includes a ball 192 which is slidably disposed in a boreprovided in an extension 194- of the shoulder 178. A leaf spring we isprovided to bias the ball 192 in the general direction of the drivepinion 132; and as is best shown in FIG. 3, leaf sprin 1% is suitablyfastened to the support plate 7% Referring to FIG. 7, the support member175' is fashioned with opposing, spaced-apart guides 1% and 290 whichdefine therebetween a slide groove 2%.? which aids in guiding the slide111 to and from the tray 4-55 under the influence of pusher arm unit 76and slide clamp unit 1%.

The main drive lever 126 additionally includes a pair of laterallyextending bracket arms 294; and as is best shown in FIG. 6, the bracketarms 2&4 receive a mounting pin 2% which is employed in securing a drivecoupling 2% to the main drive lever 126. The drive coupling 238 is utilied in applying motive force from a drive mechanism to be describedhereinbelow to the main drive lever 126. It sufiices to say at thisjuncture that drive coupling 268 is adapted to be rotated approximatelya half revolution in one direction and subsequently reversibly rotatedto its starting position.

For purposes of providing an easy understanding of the invention, it isappropriate to provide at this point a functional description of themode in which the component parts thus far identified cooperate. Theposition of the parts which is indicated generally in FIG. 5 can bedesignated the starting position. It is to be noted, in this position,that the pusher arm 78 is substantially retracted from the tray tunnel4d; and furthermore, the slide clamp unit 192 is clocked apart from thepusher arm 78 by virtue of the guide element 116 being abutted by theguides 31% and Ztlil whereby the motion of the unit 162 has beenarrested whereas the pusher arm unit 76 has been withdrawn into theconfiguration shown. This cocking apart of the slide clamp unit 1&2 isopposed by the tension springs 118 and desirably spaces the unit 1% fromthe pusher arm 78 by a distance greater than the corresponding lateraldimension of photographic slide 11. It is also to be noted, that in thisstarting position, the shutter assembly 14-8 obstructs the aperture orviewing frame 63. Thus, the light source is prevented from casting awhite spot on the viewing screen during the interlude when nophotographic slide is positioned in the viewing frame.

During the normal course of automatic operation of the slide projector,a rotation of the drive coupling 2% will be initiated in the generaldirection indicated by arrow 21%. As this rotation is initiated, hub dowill also be rotated in the direction of arrow 214 and the pusher armdrive lever will likewise rotate in that direction. As the pusher armdrive lever 83 so rotates, the cam follower 96 will tend to ride alongthe cam surface 84 whereby to permit movement of pusher arm unit 76.This movement relieves tension on spring 118 and releases the slideclamp unit 162 from its cocked position. As this occurs, the pusher arm78 will protrude slightly into the slide tray 4-3 contactingphotographic slide 111 which will be simultaneously contacted by theslide clamp 1 52, the confronting grooves 112 and 114 cooperating in aproper positioning or grasping of the slide. It is also important topoint out that the pusher arm and clamp unit are preferably movingrapidly when the slide is grasped in order to forcefully grasp the slideand prevent the slide from hanging up off-center on the clamp unit. Asis indicated in FIG. 19, movement of the pusher arm 7d is not quiteparallel to the bottom surface of the slide tray, but diverges slightlytherefrom at a small acute angle 212. This angle preferably is on theorder of 1 to 5 degrees. This movement results in a slight lifting ofthe slide rather than dragging thereof along the bottom (or side)surface of the slide tray. The lifting is not sufficient to cause thetop edge of the slide to engage the opposite surface of the slide tray.

This lifting of the slide prolongs the use-life of slides by preventingdamage to its holder when cardboard-mounted Q of the drive pinion 132.

lieved of abutment with the tooth or" the drive pinion,

aerasao 7 slides are employed. Conversely, when slides having metalframes are employed, this lifting of the slide from the slide trayprecludes the slide holder from damaging arm 78 and the slide clamp unit1&2, continuing rotation of pusher arm drive lever by means of therotation of drive coupling will bring the can follower 9*6 into theposition shown in EEG. r the process of this movement or" the pusher armdrive lever 3%, a corresponding rotation of the main drive lever 325will have relocated the tongue Eddfrorn its position as shown in FIG. 6to its position as shown in FIG. 9. This relocation of tongue 154 allowste spring 163 to alter the configuration of pawl drive lever 1% anddrive pinion pawl 15% from the position in PEG. 6 to that shown in FIG.9. This latter relocation of the drive pinion pawl 15% brings the feed p"l 374 into contact with one of the teeth on drive pi 3.32, Contactbeing on the underside of the tooth.

Continued rotation of the pusher arm drive lever from the position shownin 8 causes the earn icilower 96 to abut the end of the cam slot 8whereby to drive pusher arm unit 76 in the slanting-1y upward directionestablished by guide slotdZ the lower end portion of cam slot 184' Whenthe guide slot abuts the pusher arm spacer roller the pusher arm slidebearing will be disposed at to transition point or" cam slot Hill.Subsequent rotation of the pusher arm drive lever in the direction ofarrow will cause pusher arm unit '76 to be rotated about the spacerroller 85 and eventually the pus.-er arm s de bearing 9% v ll havetraversed the upper end portion of cam slot 163 into the positionindicated generally in FIG. 11.

During this rota on of the pusher arm unit 76, the earn follower 6 Wlllhave r en the upper portion of 0am surface 84 and the photographic slideall will have been leveled into proper position in the viewing frame 68,as shown in PEG. ll.

While the slide is being levered 'nto position in the viewing frame 68,cam follower rides up the cam surface 133 as is shown in lt 9; andapproximately at the time the slide is positioned, follower 13 5 willabut the stop whereby to rotate the shutter and inex control lever 13%?about the pivot 14 2 as is indicated in FIG. 12. This action lowers theshutter assembly 143 from its position obstructing the viewing frame asso as to allow light from the illumination source to pass through theslide, projecting the image of the slide onto an appropriatelypositioned viewing scree it is importhis tant to point out that theslide has come to rest before lowering of the shutter begins,

As the shutter assembly 1""? is being lowered, the drive pinion pawl 16%will be re acted so as to withdraw the eed pawl 17% from its positioncontacting a tooth As the feed pawl 17 is rethe tension spring res willact to draw the drive pinion pawl loll into abutment with the stopextension 32%.

This movement permits the iced pawl 17% to pass from a post 'on beneaththe tooth which it was contacting to a position a igned above but spacedaway from that same tooth.

These operations complete the half cycle of rotation in the generaldirection of arrow Sub-"salient driving of the drive coupling and con o.

-tly of hub 92 will be incurred in the general direction indicated byarrow This reverse driving will cause a i eversal of the above sequen eof steps to ta e place.

in this reverse sequence, the shutter assembly wil be raised intoposition obstructing the vi ing frame while the feed pawl 3.74 is beingurged up- 'ly cr'er the appropriate tooth on drive pinion 132, ads beingachieved under the action of cam follower 134 on the step portion of camsurface 138.

After the shutter assembly 143 closes off the aperture :53, the pusherarm unit 76 will be directed to withraw the slide from the viewingratne; and once again configuration of HG. 8 will be realized. Acontinued rotation of the drive coupling fnom this position into thegeneral direction of arrow 216 will cause tongue 15 2: to abut the pawldrive lever 15b causing it to rotate about the pivot 15%.(Iorrespondingly, drive n p" 11 will be caused to rotate about the pivotwhereby feed pawl 174 will be urged downwardly gainer the tooth or drivepinion 132 so as to rotate the riv pinion 132 against the action ofdetest 3% wherey 0 step the slide tray 48 forwardly by the distance retoposition a different slide in alignment with the usher 78.

immediately prior to the indexing of drive pinion 132, the r tatio-n orhub db and correspondingly the rotation of pusher arm drive lever in thegeneral direction of arrow are will have caused the cam follower 6 toabut the corner 22% of cam slot #34 whereby to retract the pusher armfrom the path of the slide tray 48. Simultaneously, the action offollower 96 on pusher arm unit 7s will cause the slide clamp unit 16 2to be cockedapart from the pusher anti 7% because of its abutting orstopped relationship with the ends of the support membar 175. Thus themechanism is returned to its starting position, and a full cycle ofoperation is completed. During this cycle, it is important to note, thepusher arm and the clamp unit maintain the same positional contact withthe slide that was achieved on initial grasp ing, there being no rubbingof these members along the taken.

While the specific embodiment of the slide changer mechanism hereinabovedescribed is intended for automatic projection of 2 X 2 slides, theinvention is also arranged to permit manual projection of 2 X 2 slides,2% X 2 /4 slides and standard stereo slides. The means for such manualprojection will now be described with particular reference to FIGS.21-25.

As will be seen in HQ. 21, a stereo slide guide assembly 222 is aifisedto the side of support plate 72 away rom support plate 7%. The assembly222 comprises a front plate 224, shown in FIG. 22, which is secured to aback plate 226, shown in FIG. 23, as by spot welding at appropriatepositions such as are indicated at 228. The back plate 226 is mounted tothe support plate 72 by means of a formed, gripping portion 23%, whichdefines a channel for receiving the edge of support plate 72, and amounting tab 232 which is adapted to be disposed adjacent acorresponding flange formed in the support plate 72. A suitablefastener, for example a sheet metal screw, is employed in joining thetab 232 to this corresponding flange in the support plate 72.Advantageously, oacer flanges such as flanges 234 are also provided onbacl: plate 226 in order to maintain a uniform spac ng between supportplate 72 and the stereo slide guide assembly 222, as would be desiredwhen another slide guide was to be mounted between the assembly 222 andthe support plate 72.

The front plate 224 is provided with a double-pronged spring clip whichis adapted to urge a stereo slide, such as the slide 233, against theback plate 226. The front plate 22 is preferably fashioned with achannel which cooperates with a stop 242 formed on back plate in furtherinsuring proper positioning of the slide 233 against the back plate 226.

As will ecorne apparent, when shutter assembly 148 is lowered undermanual direction in the manner to be described hereinafter, the stereoslide 233 may be readily projected by insertion hrough a slot 244 whichis fashions lamphouse 42 in alignment with the slide guide assembly 222.Either one of the stereo pair included in slide 238 may thus by manuallyprojected. Other views of the stereo slide guide assembly 222 are shownin FIGS. 14l7.

Referring for the moment to FIG. 1, the lamphouse 42 will be seen toinclude a cover plate 246 removably fastened over one portion thereof.When this cover plate 246 is removed, an aperture 248 is revealed. Thisaperture is shown in PEG-S. 21, 24 and 25 as exposing that portion ofthe slide changer mechanism immediately above the viewing frame as. Theaperture 248 facilitates manual projection of 2 x 2 slides, such asslide 250 shown in FIG. 24; and as is indicated, a slide guide assembly2:72 comprises opposing channel elements 254 and 256 for guidablyreceiving the slide 256. Channel elements 254 and 256 are fastened tothe side of support plate 72 away from support plate 74) in somesuitable manner, such as by spot welding. The slide 250 is raised andlowered from the viewing frame 68 by manually operating the shutterassembly 148, the shutter 148 being advantageously provided with a shelfportion 25% upon which the slide rests. As will become apparent, guideassembly 252 can be conveniently positioned between the stereo slideguide assembly 222 and the support plate 72.

in somewhat similar manner, a guide assembly 266, comprising two channelelements 262 and 264, may be appropriately secured to the side ofsupport plate 74 away from support plate 72. The guide assembly 26% isarranged to receive a 2% x 2% slide, such as slide 266. This combinationof elements is shown in FIG. 25.

As will be seenwith reference to FIG. 3, shutter assembly 143 isprovided with a shelf or receiver 268 spacedapart from the shelf 253;and returning to FIG. 25, the receiver 258 will be seen to cooperatewith the guide assembly 250 in accepting the 2 /4 x 2% slide 265. Aswill be recognized, manual operation of the slide changer mechanism willcause vertical movements of shutter assembly 143; and these movementswill raise and lower slide 26-6 from the viewing frame 63. Other viewsof the guide assembly zse are shown in FIGS. 14-17.

In accordance with a feature of the invention, means are provided forcorrectively editing slides being automatically projected. These meansfor rearranging or replacing slides during automatic projection includean editing lever assembly 279; and a slide carrier bracket 272, shown inFIG. 3. The slide carrier bracket 272 is adapted to be atfixed to thesupport plates 7%) and 72 above the viewing frame 63 as is shown in FIG.14. The slide carrier bracket 2'72 additionally is provided with anaperture 274 which permits access to the space between the plates in and72 and which allows extension there- I through of a slide to be edited.

As shown in FIG. 3, the editing lever assembly 270 includes two rightangularly shaped arms 2'76 and 278, these arms being appropriatelyspaced-apart by means of a cross member 2 2 and a tubular spacerarrangement 252. The arms 276 and 278 have elongated, aligned slots 23%fashioned in the generally vertically extending portions. The slotsterminate at one end in an inwardly extending enlargement 286 and at theother end in an outwardly extending enlargement 288. An editing handleis desirably affixed to the arm 273 in order to extend through anappropriate slot 222 in lamphouse 42 in order to allow manual operationof the assembly 270. This arrangement of the handle 2% and the slot 292is shown in FIG. 24.

The editing lever assembly 270 is adapted to be mounted in the supportplate assembly as with the arm 276 disposed between plate 72 and slideclamp unit 162 and with the arm 278 disposed between the support plate79 and tne slide clamp unit Hi2. FIG. 16 shows this arrangement.

A tubular spacer 294 extends between support plate 74 and support plate72 and is appropriately grooved to receive the arms 276 and 278 at theslots 284. T he editing lever assembly 27%) is also secured in thesupport vasao rib plate assembly 55 by means of an editing lever guideroller 2% which extends between the support plates 79 and 72spaced-apart from the tubular spacer 294, as is shown in FIG. 5. Theediting lever guide roller 2% is advantageously combined with adiplo-conical stop 29% which is adapted to arrest the motion of slideclamp unit 1492 and to hold it centered and in alignment.

When the slide changer mechanism hereinabove described is being operatedfor automatic projection of a quantity of photographic slides, theediting lever assembly 27% may be manipulated as follows for purposes ofediting.

When a photographic slide has been levered into the position showngenerally in FIG. 11 and it is discovered that this slide is upside downor otherwise improperly arranged, or if it is desired to replace theparticular slide with another, the slide changer mechanism will first bereleased from the drive in a manner to be described hereinbelow.Subsequently, the editing handle 299 will be manually lowered from itsnormal position in the upper reaches of slot 292 as shown in FIG. 24;and when the handle 29% has been directed to the lower reaches of slot292, the assembly 27% will have been lowered a corresponding distance.At this time, the arm portions carrying the cross member 80 will be seenobstructing the viewing frame 68. In this position, the photographicslide 111 will be held between the end of pusher arm 78 and slide clampunit 1%2. Additionally, the spacer 232 of editing lever assembly 27cwill be in contact with the rearwardly extending hook portions 3% ofslide clamp unit 102.

A subsequent manual operation of the slide changer mechanism will causethe shutter assembly 148 to be upraised in its normal manner. However,as pusher arm 78 is retracted slide clamp unit 102 will be unable tofollow freely because of the engagement of book portions 390 with thespacer 282. The springs 118 will, nonetheless, act on the slide clampunit Hi2; and sufficient freedom is allowed to cause a grasping of theslide between the slide clamp unit 132 and the cross member 236, as isshown generally in FIG. 20,

Further manual operation of the slide changer mechanism will incur alifting of the slide through the aperture 274 in slide carrier bracket272, the pivoting of pusher arm unit 76 about pusher arm spacer roller86 incurring a vertical movement of the slide clamp unit 262 inaccordance with the arcuate movement of bearing 106.

When the slide 111 is projecting above carrier bracket 272, it may beeasily grasped by hand; and because of the resiliency of springs 118,the slide 111' may be easily withdrawn, rearranged and replaced orsubstituted for by a different slide. When the slide is being returned,it is to be urged with a slight pressure against the unit 102, presseddownwardly into contact with the receiver 116 and then released to begrasped against the cross member 28%? by the action of springs 118 onunit 192. Subsequent manual operation of the slide changer mechanismwill lower the shutter assembly 143 as well as the editing leverassembly 276. Simultaneously, the pusher arm 78 will be positionedconfronting the edge of the slide opposite the pusher arm unit 1&2.

Next, the editing lever assembly 27% may be directed upwardly into itsnormal position by manually urging the handle 2% into the upper reachesof slot 292. As the assembly 27% reaches this normal position, the enlargement 288 will come into alignment with the spacer 224.Advantageously, engagement of the spacer 234 and the enlargement 233 isincurred by suitable means'biasing the lower end of the editing leverassembly 276 in the general direction of tray tunnel46.

In one specific embodiment of the invention, this biasing means hasincluded a crank 322 and a tension spring 394. As shown in FIG. 4, thecrank 3S2 enters aligned bores in the platform portion 58 and in thepiano hinge 306 by which the lamphouse 42 is swingably mounted. to

aoraeto it the projector structure d0. Being rotatably mounted in thesealigned bores, the crank 3 3 2 may be adapted to confront the outer edgeof editing lever assembly 27% whereby the tension spring 384 connectedbetween plate 72 and crank 392 can develop the desired bias. As will herecognized, engagement of the spacer 2% and the enlargement 288effectively locks the editing lever assembly 279 in its normal positionwherein it is arranged to clear viewing frame 68 and avoid interferencewith the automatic operation of the slide changer mechanism.

Considering now FIGS. 2 and 26-33 for a description of the drivemechanism of the invention, the drive coupling 203, referred tohereinabove, will be receiving an operating shaft 368 Within an axialbore 31% (PEG. 32). Advantageously, coupling 2% is provided with axiallyelongated, radially extending, diametrically disposed slots 312 in whicha pin 314 is adapted to ride. The pin 3-14 is secured to shaft 3433adjacent one end; and the slots 312 provided in coupling 2% are arrangedto be of sufiicient length to permit engagement and disengagement of adog clutch 316.

The operating shaft 398 extends freely and slidably through a femalemember 318 of the clutch 316, while the shaft 3% is advantageously keyedto the male member 32%} by means of a pin 322. A compression spring324'is located between the male member 320 and a washer 32s which isaffixed to shaft 358. Spring 324 biases the memher 320 in the generaldirection of member 318. Additionally, the member 325 is fashioned withaxially elongated, radially extending, diametrically disposed slots 328through which the pin 322 passes.

Thus, the operating shaft 398 may be urged in the general direction ofsupport plate assembly -6; and if the tongue portions 336 of member 32!}fail to engage the slot 332 in member 313, the slots 328 will permitmovement of the shaft whereby subsequent relative rotation between themember 329 and the member 318 will align the tongues 33! and the slot332. In this alignment, spring 324 will cause an engagement of theclutch.

The operating shaft 3% extends slidably and rotatably through a bush 334provided in the sidewall of projector structure 4%) to have an editingknob 336 fastened to its otherwise free end. Knob 336 is preferablyknurled in or- .der to facilitate its use in manually engaging anddisengaging the clutch 315. A shaft detent bracket 333 is also seured tothe bush 334-, as by self-tapping screws 34%). Detent bracket 33%carries a formed end-portion 342 which cooperates with the spaced-apart,circumferential grooves 344 and 346 which are fashioned in shaft 3% inorder to provide positive location of clutch 316 into the engaged, orimminently engaged, position and into the disengaged position.

As will be recognized, a disengagement of clutch 316 permits rotation ofthe drive coupling 2% under manual rotation of editing knob 336. Thismanual rotation of drive coupling 2% is desired in the manual projectionof 2 x 2 slides and the manual projection of 2 /4 x 2%. slides as wellas in the editing operation, according to the descriptions givenhereinabove.

Beneath the platform portion 58 of projector structure 46, juxtaposedwith the operating shaft 398 and the support plate assembly 56, a drivemotor 348 is secured to the lower surface of the floor of tray tunnel 46as by motor support brackets 35% and 352. This arrangement is best shownin FIG. 26. The brackets 35d and 352 also support a cam shaft 354 inrotatable relationship parallel to the operating shaft 3% and the outputshaft 35a of drive motor 348.

The output shaft 356 is provided with circumferential grooves which areadapted to mesh with corresponding ridges provided on a drive belt 353which connects the shaft 356 with a. drive gear and pulley 36%.

As is best shown in FIG. 32, with secondary reference to FIGS. 28 and29, the drive gear and pulley 365 is rotatably mounted on shaft 354 andextends a hub portion 362 a motion necessary for operating shaft 393.

through an aperture 3nd provided in the support bracket 352. A sun gear366 is integrally formed with hub 3-62 and is adapted to mesh with anddrive a number of planet gears 358, the planet gears 36S meshing with aring gear 379 which is fixed to the support bracket 352. The planetgears 368 rotate freely on stub shafts or axles 372 which are molded toextend axially from the face of a rotating planet gear carrier 374.Thus, the rotation of pinion 366 is suitably reduced and transmitted tothe gear carrier 374.

Gear carrier 3'7 is fixed in driving relationship to cam shaft 354, asby pinning or other suitable means, and is adapted to mesh with anintermediate spur gear 376 which is rotatably mounted to the supportbracket 352 at a location spaced-apart from cam shaft 354.

A segment gear 378 is mounted to rotate freely about the hub 38d ofplanet gear carrier 374 and is fashioned with a cam slot 382. A follower384 which is eccentrically disposed in axially extending relationship onintermediate spur gear 376 is arranged to ride in the cam slot 382 inorder to incur an oscillatory rotation of the segment gear 378. Thesegment gear 3-73 advantageously meshes with an auto drive pinion 386which is molded integrally with the female element 318 of dog clutch316. This engagement allows drive motor 343 to rotate the operatingshaft 3% and concomitantly the coupling 2%. Because of the arrangementof the gear drive and the segment gear 378, motor 34% incurs the cyclic,reversibly rotatable movement of drive coupling 298 which has beenreferred to hereinabove as necessary to the proper operation of theslide changer mechanism.

The integral formation of drive pinion 38d and the female clutch member32.8 is shown in FIG. 33. Also indicated in FIG. 33 is an elongatedportion 388 which carries a circumferential groove 39%. A back-up member392 is secured to bracket 352 in offset relationship in order to ride inthe groove 3% and thereby support member 318 against the force involvedin engaging the clutch. Female clutch member 313 is preferably made witha serrated insert 393 that permits precise adjustment of the oscillatorymotion of segment gear 378 with the reciprocating After properadjustment, the member 313 and insert 3% are connected or fused togetherto form a single assembly.

Turning now to FIGS. 26 and 32, a multiple switching cam 394 is shownfixed to the cam shaft 354 in order to operate switch blades 3% and 397included in a cycling unit assembly 398. Assembly 3% is suitably mountedto the control panel element as. Another switch blade 399' is includedin the assembly 3% to be operated by a timer earn 4%. The cam ttltl isrotatably mounted to the cam shaft 354 by means of a collar portion $32,the portion 4 2 terminating in an eccentric arm idd which is adapted tobe engaged by a pin 4%. Pin 4% is fixed to the shaft 354 in radiallyextending relationship.

Ann 4534 passes through an appropriate slot in a link 4% which ispivotally connected to the piston of a dash pot 410. Referring to FIGS.26 and 31, tension springs 412 are stretched between the link .98 and atimer spring bracket 41 in order to bias the piston of dash pot 410 inthe general direction of the bottom of the dash pot cylinder; and as isbest shown in FIG. 31, the dash pot 410 extends into the interior ofcontrol panel element at to be regulated by a timer adjusting knob 416thereby altering the speed at which the projector will be operated.

The slide projector of the invention is advantageously controlled forautomatic operation through the rotation of multiple switching cam 394and timer cam 4%, the action of these cams being realized on thecorresponding switch blades in the cycling unit assembly 398. When it isdesired to operate the projector semi-automatically, suitable controlelements such as manual change knob 418 may be employed to alter themanner in which the several switches operate. For example, as is shownin FIG. 30, the manual change knob 438 is adapted to close the switchcontacts associated with switch blade 3 96 under manual direction. Eachdepression of change knob 413 results in a half-cycle operation of theprojector. Thus, a first press of the knob can result in moving a slideinto position whereas the next press of the knob can result in returningof the slide to the tray.

As will be seen from an inspection of FIG. 26, a squirrel cage fan 42%is advantageously disposed within the projector structure 45) with anoutlet portion 422 emptying through the roof of structure 59 adjacentthe light source whose socket is indicated at 424. The fan and the lightsource are operated in conjunction with drive motor 3 3 in accordancewith the circuitry illustrated in FIG. 2. There, the motor of fan 42%)is indi cated generally at 426, and the lamp or light source for theprojection system is shown at 428.

Continuing with reference to FIG. 2, a wall plug 435 will be seenprovided for connecting the electrical system of the invention to asource of electrical energy, conveniently the customary householdsource. The leads from plug 43%) are coupled respectively to a connectorblock 432 and to a master switch panel 434, panel 434 being suppliedwith switch buttons 436, 4-33 and 440 which extend slidably through thecontrol panel element 44 for facility in their operation.

The switch 436 is adapted to energize lamp 428 and the connector block432. Through energization of block 432, a circuit is completed to fanmotor 426 and to a panel light 4-42 which is arranged in parallelwith/or on a tap of the fan motor. Energization of block 432 alsoconditions the circuit to drive motor 438 for its operation incompliance with the operation of the switches contained in assembly 398under the influence of switching cam 394 and timer cam dill If desired,a remote control means, not shown, may cooperate with the assembly 3% inthe operation of drive motor 3-48 as by being connected into the circuitat a receptacle 444. In addition, there may be provided a receptacle 445by the use of which room lighting may be inserted in the circuitry ofthe projector whereby switch 436 may be operated to deenergize the roomlights when the lamp 428 of the projector is energized.

Operation of switch 538 is directed to deenergize lamp 423 andenergizing the room lights while leaving fan motor 426 and drive motor348 operating. Moreover, switch is adapted to energize the room lightsconnected through receptacle 445 while simultaneously deenergizing fanmotor 426 and drive motor 343, motors 426 and 348 being arranged foroperation in unison.

When the assembly 393 is conditioned for operation by switch 436, acomplete cycle of operation will be incurred as follows from thestarting position of the slide changer mechanism which has beendescribed hereinabove with reference to FIGS. 5 and 6. In this position,the switch contacts associated with blades 397 and 3% will be closed toenergize motor whereas the contacts associated with blade 3% will beopen.

Subsequently, a rotation of cam shaft 354- will cause pin 4% to pick uparm 49 5-. Continued rotation of the cam shaft will cause cam 394 toclose the contacts associated with blade 3%. Shortly thereafter, thephotographic slide will be positioned in the viewing frame es; and asthe operating shaft 368 continues to be driven under the influence ofsegment gear 378, cam 394 will be directed to open the switch contactsassociated with blades 3% and 39?. Thereupon, arm 484 will overcentercam shaft 354 whereby springs 412 will urge the piston into the bottomof the cylinder of dash pot are.

As timer cam 4th} is being thus rotated under the influence of springs$12 and dash pot all), motor 343 will have been'brouglit to a halt whilethe photographic slide is in the viewing frame and while the shutterassembly 148 is lowered into its non-obstructing position.

Finally under the influence of dash pot 41d and springs 412, cam deliwill engage blade 399 to close the contacts sociated therewith in orderto energize drive motor 343 and drive segment gear 373 in the reversedirection.

id The multiple switching earn 394 will thereafter assume control ofdrive motor 348 through the contacts associated with switch blades 3%and 397 to complete the cycle and return the various elements to theirstarting position.

While a particular embodiment of the invention has Y een shown, it is tobe understood, of course, that the invention is not limited theretosince many modifications may be made; and it is, therefore, contemplatedto cover any such modifications as fall within the true spirit and scopef the appended claims.

The invention is claimed as follows:

1. in a slide projector, the combination. comprising: support platemeans defining cam slot means and a viewframe; pusher arm means arrangedwith said support plate means, includin slide bearing means adapted toride in said cam slot means, to cooperate in arcuately transferring aslide receivable in a slide tray to and from said viewing frame; clampmeans confronting said pusher arm means in variably spaced-apartrelationship transversely of said slide tray for selective gripping of aslide therebetween; mechanical means operably connecting said pusher armmeans and said clamp means for transporting said pusher arm means andsaid clamp means as a relatively rigi unit when a slide is grippedthereby and for tiltable lifting of said slide from said slide tray andtiltable replacement thereof; indexing means on said support plate meansadapted to advance said slide tray incrementally, said indexing meansdefining a stop abuttable with said clamp means'for cocking-apart saidclamp means and said pusher arm means whereby to release said slide;shutter means slid-ably afiixed to said support plate means forselectively obscuring the aperture of said viewing frame; control meanspivotally mounted to said support plate means for operating said shuttermeans and for stepping said index ing means; and cyclically operabledrive means for reversibly operating said mechanical means and saidcontrol means.

2. in a slide projector, the combination comprising: support plate meansdefining a viewing frame; pusher arm means arranged with said supportplate means to cooperate in arcuately transferring a slide receivable ina slide tray to and from said viewing frame; clamp means confrontingsaid pusher arm means in variably spacedapart relationship transverselyof said slide tray for selective gripping of a slide therebetween, saidclamp means having offset means defining a hook; mechanical meansoperably connecting said pusher arm means and said clamp means fortransporting said pusher arm means and said clamp means as a relativelyrigid unit when a slide is gripped thereby and for tiltable lifting ofsaid slide from said slide tray in tiltable replacement thereof; amanually operable editing lever assembly fior manipulating a slidepositioned in said viewing frame, including pin means releasabiyengageable by said hook for directing said clamp means to eject a slidefrom said viewing frame; and cyclically operable drive means forselectively and reversibly operating said mechanical means.

3. In a slide projector, the combination comprising: support plate meansdefining a viewing frame; pusher arm arranged with said support platemeans to cooperate in transferring a slide receivable in a slide tray toand from said viewing frame; clamp means confronting said pusher armmeans in spaced-apart relationship transversely of said slide tray forselective gripping of a slide therebetween; mechanical means operablyconnecting said pusher arm means and said clamp means for transportingsaid pusher arm means and said clamp means as a relatively rigid unitwhen a slide is gripped thereby and for tiltable lifting of said slidefrom said slide tray and tiltable replacement thereof; slot-and-guidemeans associated with said support plate means for manual reception ofphotographic slides; shutter means slidably affixed to said supportplate means for selectively obscuring the aperture of said viewingframe, said shutter means i defining shelf means cooperabie with atleast a portion of said slot-and-guide means in projecting slidescontained therein; control means pivotally mounted to said support platemeans for operating said shutter means; and cyclically operable drivemeans for selectively and reversibly operating said mechanical means andsaid control means.

4. in a slide projector, the combination comprising: support plate meansdefining cam slot means and a viewing frame; pusher arm means arrangedwith said support plate means, includirn slide bearing means adapted toride in said cam slot means, to cooperate in arcuately transferring aslide receivable in the slide tray to and from said viewing frame; clampmeans confronting said pusher arm means in variably spaced-apartrelationship transversely of said slide tray for selective gripping of aslide therebetween; mechanical means operably connecting said pusher armmeans and said clamp means for transporting said pusher arm means aidsaid clamp means as a relatively rigid unit when a slide is grippedthereby and for tiltable lifting of, said slide from said slide tray andtiltable replacement thereof; indexing means on said support plate meansadapted to advance said slide tray incrementally, said indexing meansdefining a stop abuttable with said clamp means for cocking-apart saidclamp means and said pusher arm means whereby to release said slide;shutter means slidably afiixed to said support plate means forselectively obscuring the aperture of said viewing frame; control meanspivotally mounted to said support plate means for operating said shuttermeans and for stepping said indexing means; and cyclically operabledrive means for reversibly operating said mechanical means and saidcontrol means, said pusher arm means and said clamp means havingV-shaped grooves confront ing each other for the gripping of said slide.

5. In a slide projector, the combination comprising: a slide changermechanism; axially movable, operating shaft means for said slide changermechanism; clutch means on said operating shaft means, including twoclutch elements, engageable and disengageable by axial movement of saidoperating shaft means; a driven shaft rotatably mounted parallel to saidoperating shaft means; a reversibly oscillatory member pivotally mountedabout sm'd driven shaft and adapted to mesh with one of said clutchelements in toothed engagement, said member defining a cam slot; gearmeans arranged to be driven by said driven shaft; cam follower meansarranged with said gear means and adapted to ride in said cam slot tooscillate said member in response to the rotation of said driven shaftwhereby to drive said operating shaft means when said clutch means isengaged; and motive means for said riven shaft.

6. In a slide projector, the combination comprising: a slide changermechanism; operating shaft means for said slide changer mechanism; gearmeans on said operating shaft means; a cam shaft rotatably mountedparallel to said operating shaft means; a reversibly oscillatory memberpivotally mounted about said cam shaft and adapted to mesh with saidgear means in toothed engagement, said member defining a cam slot;planetary gear means arranged to be driven by said cam shaft; camfollower means arranged with said gear means and adapted to ride in saidcam slot to oscillate said member in response to the rotation of saidcam sha t; motive means for said cam shaft; slide projector meansassociated with said changer mechanism; switch means for said slideprojector means disposed adjacent said cam shaft; and a plurality ofcams and on said cam shaft adapted to operate said switch meansselectively.

7. in a slide projector, the combination comprising: a slide changermechanism; operating shaft means for said slide changer mechanism; gearmeans on said operating shaft means; a cam shaft rotatably mountedparallel to said operating shaft means; a reversibly oscillatory memberpivotally mounted about said cam shaft and adapted to mesh with saidgear means in toothed engagement, said all) i l ranged to be driven bysaid cam shaft; cam follower means arranged tn said planetary gear meansand adapted to de in sale. cam slot to oscillate said member in responsethe rotation of said cam shaft; motive means for said cam shaft; slideprojector means associated with said changer mechanism; switch means forsaid slide projector means disposed adjacent said cam shaft; a pluralityof cams on said cam shaft, at least one of which is fixed to said camshaft and at least one of which is partially free to r e thereabout,said cams being adapted to operate mounted parallel to said operatingshaft means; a reversibly oscillatory member pivotally mounted aboutsaid cam shaft and adapted to mesh with one of said clutch elements intoothed engagement, said member defining a cam slot; planetary gearnieans arranged to be driven by said cam shaft; cam follower meansarranged with said gear means and adapted to ride in said cam slot tooscillate said memher in response to the rotation of said cam shaftwhereby to drive said operating shaft means when said clutch means isengaged and whereby not to drive said shaft means when said clutch meansis disengaged; motive means for said cam shaft; slide projector meansassociated with said changer mechanism; switch means for said slideprojector means disposed adjacent said cam shaft; 21 plurality of camson said cam shaft at least one of which is fixed to said cam shaft andat least one of which is partially free to rotate thereabout, said camsbeing adapted to operate said switch means selectively; and escapementmeans, including a dash pot arranged with said partially free cam totime operation of the corresponding switch means.

it a slide projector, the combination comprising denning a viewingframe, slide supporting means lug a slide in a position to betransferred to said viewing frame, said slide supporting means having asubstantially fiat slide supporting surface, pusher arm means movablebetween said slide supporting means and said vi wing frame to transfer aslide from one to another thereof, backup means operatively connected tosaid pusher arm means for cooperation with said pusher arm meansclampingly to support a slide for edgewise moveient thereofsubstantially in its own plane, said pusher arm means and said backupmeans coacting as a relatively rigid unit when a slide is grippedthereby, and guide means for said pusher arm means, said guide means atleast in part being disposed to effect movement of said pusher arm meansat a small acute angle relative to said slide supporting meanssupporting surface, whereby a slide clamped between said pusher armmeans and said backup means is lifted slightly from said supportingsurface and is moved divergingly relative thereto upon transfer fromsaid supporting means to said viewing frame and vice versa.

10. In a slide projector, the combination comprising base means, meanson said base means providing a pro jecting station, pusher arm meansmovably mounted from said base means for movement toward and away fromsaid projecting station to transfer a slide to and from said projectingstation, clamp means disposed substantially opposite to said pusher armmeans in spaced apart confronting reiation thereto for selectivegripping of a slide therebetween, means operatively connecting saidpusher arm means and said clamp means to move said clamp means and saidpusher arm means relatively toward one another to grip a slidetherebetween and for thereafter maintaining said pusher arm means andsaid clamp means as a relatively rigid unit when a slide is grippedthereby, means operatively connected between said unit and said basemeans for moving said unit in a direction away from the direction ofsaid clamp means and back again, and cyclically operable drive means foroperating said moving means.

11. In a slide projector, the combination set forth in claim 10 andfurther includin spring means urging said clamp means toward said pusherarm means, and stop means engaged by said clamp means upon movement ofsaid pusher arm means and said clamp means away from said projectingstation, said stop means elfecting movement of said clamp means awayfrom said pusher arm means to release a slide.

12. In a slide projector, the combination comprising base means, meanson said base means providing a projecting station, pusher arm meansmovably mounted from said base means for movement toward and away fromsaid projecting station to transfer a slide to and from said projectingstation, clamp means disposed substantially opposite said pusher armmeans in spaced apart confronting relation thereto for selectivegripping of a slide therebetween, means operatively connecting saidpusher arm means and said clamp means for gripping a slide between saidpusher arm means and said clamp means and for holding said pusher armmeans and said clamp means as a substantially rigid unit, means formoving said unit relative to said base means first rectilinearly andthen pivotally to said projecting station in a direction away from thedirection of said pusher arm means and in the direction of said clampmeans and back again, and cyclically operable drive means for op eratingsaid moving means.

13. in a slide projector, the combination comprising base means, meanson said base means providing a projecting station, pusher arm meansmovably mounted from said base means for movement toward and away fromsaid projecting station to transfer a slide to and from said proiectingstation, clamp means disposed substantially opposite said pusher armmeans in spaced apart confronting relation thereto for selectivegripping of a slide therebetween, means operatively connecting saidpusher arm means and said clamp means for gripping a slide between saidpusher arm means and said clamp means and for holding said pusher armmeans and said clamp means as a substantially rigid unit, means formoving said unit along a path which is at least in part nonlinear, tosaid projecting station in a direction away from the direction of saidpusher arm means and in the direction of said clamp means and backagain, and cyclically operable drive means for operating said movingmeans.

14. In a slide projector, a combination comprising base means, means onsaid base means providing a projecting station, slide carrying means forcarrying a slide along a predetermined path to and from said projectingstation, said slide carrying means incluning a first clamp memberdisposed remotely of said projecting station and generally facing towardsaid station and a second clamp member disposed intermediate the firstclamp member and the projecting station and confronting the first clampmember, said clamp members being relatively movable toward and away fromone another alternately for gripping and for releasing or receiving aslide, means coacting between said two clamp members for moving said twoclamp members relatively toward one another to grip a slide andthereafter to retain said clamp members as a relatively rigid unit, andmeans for moving said unit toward and away from said projecting station.

15. in a slide projector, the combination set forth in claim 14, thecoacting means comprises means pivotally interconnecting the two clampmembers.

16. in a slide projector, the combination comprising base means, meanson said base means providing a projecting station, means on said basemeans providing a slide supplying station spaced from said projectingstation, slide transporting means mounted for movement between saidsupplying station and said projecting station and back again,cooperating guide means on said base and on said transporting means forguiding said transporting means initially with a rectilinear movementand subsequently with a pivotal movement to transfer a slide from saidsupplyin station to said projecting station, and drive means actingbetween said base means and said transporting means for moving saidtransporting means from said supplying station to said projectingstation and back again.

17. The combination set forth in claim 16 wherein the guiding meanscomprises a pair of guide tracks one of which is straight and terminatedby a positive stop, the other of which has a portion which is straightand substantially parallel to the first guide track, and a secondportion which is angularly disposed relative to the first portion.

18. In a slide projector, the combination comprising base means, meanson said base means providing a projecting station, means on said basemeans providing a slide supplying station spaced from said projectingstation, said slide supplying station having a slide supporting surface,slide transporting means mounted for movement between said supplyingstation and said projecting station and back again, means coac-tingbetween said base and said transporting means for guiding saidtransporting means initially and substantially along said slidesupporting surface and at a shallow angle to said surface and awaytherefrom and drive means acting between said base means and saidtransporting means for moving said transporting means from saidsupplying station to said projecting station and back again.

References Cited in the file of this patent UNITED STATES PATENTS1,371,871 Dietz Mar. 15, 1921 2,579,281 Tuck Dec. 18, 1951 2,398,807Ewald Aug. 11, 1959 2,909,898 Briskin Oct. 20, 1959 2,949,814 Boughtonet al. Aug. 23, 1960 FOREIGN PATENTS 1,158,069 France Jan. 13, 1938

1. IN A SLIDE PROJECTOR, THE COMBINATION COMPRISING: SUPPORT PLATE MEANSDEFINING CAM SLOT MEANS AND A VIEWFRAME; PUSHER ARM MEANS ARRANGED WITHSAID SUPPORT PLATE MEANS, INCLUDING SLIDE BEARING MEANS ADAPTED TO RIDEIN SAID CAM SLOT MEANS, TO COOPERATE IN ARCUATELY TRANSFERRING A SLIDERECEIVABLE IN A SLIDE TRAY TO AND FROM SAID VIEWING FRAME; CLAMP MEANSCONFRONTING SAID PUSHER ARM MEANS IN VARIABLY SPACED-APART RELATIONSHIPTRANSVERSELY OF SAID SLIDE TRAY FOR SELECTIVE GRIPPING OF A SLIDETHEREBETWEEN; MECHANICAL MEANS OPERABLY CONNECTING SAID PUSHER ARM MEANSAND SAID CLAMP MEANS FOR TRANSPORTING SAID PUSHER ARM MEANS AND SAIDCLAMP MEANS AS A RELATIVELY RIGID UNIT WHEN A SLIDE IS GRIPPED THEREBYAND FOR TILTABLE LIFTING OF SAID SLIDE FROM SAID SLIDE TRAY AND TILTABLEREPLACEMENT THEREOF; INDEXING MEANS ON SAID SUPPORT PLATE MEANS ADAPTEDTO ADVANCE SAID SLIDE TRAY INCREMENTALLY, SAID INDEXING MEANS DEFINING ASTOP ABUTTABLE WITH SAID CLAMP MEANS FOR COCKING-APART SAID CLAMP MEANSAND SAID PUSHER